Method of and apparatus for producing liquid impregnated fibrous material

ABSTRACT

A liquid-impregnated fibrous material is produced by feeding the material forward in the form of the closed loop. An impregnating liquid is applied to the loop over a chosen portion of the loop. The material approaching the loop and the material receding from the loop are maintained in contact with one another over a chosen distance.

United States Patent Gailey et a1.

METHOD OF AND APPARATUS FOR PRODUCING LIQUID IMPREGNATED FIBROUS MATERIAL Inventors: Robert McNaught Gailey; Joseph John Hurley, both of Paisley,

Scotland Assignee: ,I. & P. Coats, Limited, Glasgow,

Scotland Filed: Jan. 21, 1974 Appl. No.: 435,269

Related US. Application Data Division of Ser. No. 261,956, June 12, 1972, abandoned.

Foreign Application Priority Data June 17, 1971 United Kingdom 28362/71 U.S. Cl. 118/325; 118/56; 118/124; 118/405; 118/420 Int. Cl. B050 5/00 Field of Search 118/325, 419, 423, 56,

1 June 17, 1975 [56] References Cited UNITED STATES PATENTS 1,845,317 2/1932 Moone 1 18/419 2,040,514 5/1936 Dillon 118/419 2,555,673 6/1951 Beatty 118/419 2,558,734 7/1951 Cresswell 118/420 2,618,575 11/1952 Oswin 118/405 2,659,343 ll/1953 Kucher 118/419 2,846,975 8/1958 Hennessey.. 118/419 3,032,813 5/1962 Stalego 118/325 Primary ExaminerLouis K. Rimrodt Assistant ExaminerDouglas Salser Attorney, Agent, or Firm-Larson, Taylor and Hinds [57] ABSTRACT A liquid-impregnated fibrous material is produced by feeding the material forward in the form of the closed loop. An impregnating liquid is applied to the loop over a chosenportion of the loop. The material approaching the loop and the material receding from the loop are maintained in contact with one another over a chosen distance.

9 Claims, 5 Drawing Figures METHOD OF AND APPARATUS FOR PRODUCING LIQUID IMPREGNATED FIBROUS MATERIAL This is a division of application Ser. No. 261,956, filed June 12, 1972, now abandoned.

The subject of this invention is a method of and apparatus for producing liquid-impregnated fibrous material.

In many manufacturing processes it is necessary to impregnate fibrous material with an excess of a liquid and then subsequently remove a large proportion of the impregnating liquid.

The fibrous material may be in a form such as thread and yarn and woven fabric and may be a natural material such as cotton, jute and hemp and artificial material such as nylon and polyester.

The normally known method of removing the impregnated material is to squeeze, scrape or brush the material after the original dry material is impregnated with an excess of the impregnating liquid, and the normally known apparatus for performing the known method contains squeeze rollers and/or scraper blades and/or brushes or other apparatus capable of squeezing, scraping or brushing the material.

There are certain impregnating liquids for which such apparatus is fairly satisfactory but there are other impregnating liquids which cause difficulties. For example, starch solutions which are used for sizing purposes are sticky and tend to congeal on rollers, blades and brushes. Even watery solutions soon render roller blades and brushes so wet that most of the wiping or scraping action is lost, while some impregnating liquids must be used either at a temperature high enough to damage the material of rollers, blades, brushes and other apparatus normally used or at a temperature low enough to cause too great a reduction in the necessary resiliency of the squeeze rollers, scraper blades, brushes and other apparatus normally used. Even at normal temperatures the apparatus currently used can damage the fibrous material for example by changing the surface finish or by causing wear, and/or by introducing undesirable stresses in the material. In all cases abrasion on the rollers blades and brushes causes them to wear very rapidly. The amount of liquid removed thus varies continuously in a cycle which extends from the time one set of new rollers, blades or brushes is fitted to the time the next set of rollers blades or brushes is fitted. This causes great difficulties in recovery because the load on the recovery plant is continuously varying.

In addition to the difficulties just stated there is the added difficulty that impregnating liquids are almost always dangerous to health or a hazard to public safety and/or are expensive so that they cannot merely be allowed to run to waste but must be recovered. Also, many processes which require impregnation of a fibrous material with a dangerous and/or expensive liquid and which are completely viable in themselves are not at present being practised because the recovery of the impregnating liquid requires such large and expensive plant that the cost of providing and operating the recovery plant would completely override the viability of the process and would either render the whole operation including recovery of the impregnating liquid too expensive for commercial exploitation or would raise the cost of the treated articles to a level above that commercially acceptable. Thus for long it has been an aim to find a means of recovering and/or reusing liquids used in impregnating fibrous materials without the necessity for providing a costly recovery plant.

It is an object of the present invention to provide a process and apparatus for producing a fibrous material which has been first impregnated with an excess of an impregnating liquid and has then had a large proportion of the impregnating liquid removed.

A method according to the invention consists in feeding fibrous material from a supply of unimpregnated material continuously forward in the form of a closed loop, maintaining the material approaching the loop and the material receding from the loop in contact for a chosen distance and applying an impregnating liquid to the material over a chosen extent of the loop.

The material approaching the loop and the material receding from the loop may lie side by side in mutual contact or may simply cross one another.

Where the material approaching the loop and the material receding from the loop lie side by side they may be arranged to move alternatively in the same or opposite directions.

Apparatus for performing the method incorporates feeding means for feeding material forwardly, means for guiding it to remain in the form of a loop, means for maintaining the material approaching the loop and the material receding from the loop in contact and means for applying impregnating liquid to the loop over a chosen extent of the loop.

The means for feeding the material may consist of feed rollers which may where desired be located at positions where they are unaffected by the impregnating liquid ie at a point after the impregnating liquid is finally removed or rendered harmless, e.g. by dilution or drying and, it may be, at a point before the material approaching the loop and the material receding from the loop come into contact.

The means for maintaining the material in the form of a loop may be at least one guide bar or at least one guide wheel or at least one guide roller around which the material is led.

The means for maintaining the material approaching the loop and the material receding from the loop in crossing contact may be a single ring through which the material approaching the loop and the material receding from the loop pass from opposite sides.

The means for maintaining the material approaching the loop and the material receding from the loop in side by side contact over a chosen distance may be two spaced rings through each of which the material approaching the loop and the material receding from the loop pass from the same side.

Where the material approaching the loop and the material receding from the loop move in the same direction while in contact the means for maintaining the approaching material and the receding material in contact may be grooved pulleys both of which may be freely rotatable or one of which may be driven, the other being freely rotatable.

To cause the material on its way to the loop and the material on its way from the loop to move for a certain distance in the same direction the material on its way to the loop or the material on its way from the loop is reversed in direction eg by a system of guide bars or pulleys.

The means for applying an impregnating liquid to the loop over a chosen extent of the loop may be a bath into which the loop dips or said means may be a spray nozzle connectible to a supply of impregnating liquid and operable to spray impregnating liquid against the loop.

Practical embodiments of the invention are illustrated in the accompanying semi-diagrammatic drawings in which FIG. 1 shows a basic form of the apparatus of the invention utilizing a ring,

FIGS. 2 and 3 illustrate another embodiment of the apparatus of the invention and FIGS. 4 and 5 show yet another embodiment of the apparatus of the invention.

In the drawings 1 denotes fibrous material in the form of yarn formed into a loop 2. 3 denotes material approaching the loop and 4 denotes material receding from the loop. 5 denotes a pulley serving as the means for guiding the material to remain in the form of the loop 2 and 6 denotes a receptacle filled with liquid 7, the receptacle 6 constituting the means for applying impregnating liquid to the loop 2 over a chosen extent of the loop 2. 8 denotes feeding means for feeding the material forwardly.

Referring particularly to the construction illustrated in FIGS. 1, 9 denotes a ring through which the material 3 approaching the loop 2 and the material 4 receding from the loop 2 pass from opposite sides, the material 3 and the material 4 crossing in contact with one another within the ring 9 so that the ring constitutes the means for maintaining the material approaching the loop and the material receding from the loop in contact.

Referring to FIGS. 2 and 3, arms 10 and 11 are pivoted at the points 12 and 13 respectively and are swingable towards and from one another so that the ends 10A and 11A of the arms 10 and 11 press the material 3 and the material 4 together at two vertically spaced points as illustrated in FIG. 3 so that the material is kept in contact over the distance between the points 10A and 11A. In this construction 14 denotes a guide tube for approaching material 3 and 15 denotes a bracket supporting the arms 10 and 11 and also a pulley 16 around which the receding material 4 is led on its way to the feeding means 8.

In the construction of FIGS. 4 and 5, an arm 17 is pivoted at 18 to a fixed bracket 19 carrying a guide pulley 20 and supports a pulley 21 around which the receding material 4 is led to the feeding means 8. The bracket 19 is supported on a column 22 which supports a pulley 23 and the pulley 5. The pulley 20 and the pulley 23 serve as the means for maintaining the material 3 and the material 4 in contact when the device is in operation. 24 denotes a guide passage provided in the bracket 19 for the approaching material 3.

In practice and referring first to FIG. 1, the dry material 3 approaching the loop 2 in passing through the ring 9 comes into contact with the material 4 receding from the loop and which is already impregnated with liquid it has picked up from the liquid 7 in the receptacle 6. The ring 9 maintains the material 3 and 4 in contact and as the material 3 and the material 4 pass one another in contact almost all of the liquid carried by the material 4 receding from the loop 2 is transferred to the material 3 approaching the loop 2. The material 3 after passing through the ring 9 thus carries most of the liquid previously in the material 4 when it enters the liquid 7 in the receptacle 6 and the liquid applied to the material 3 in the receptacle 6 is actually only what is necessary to compensate for the small quantity of liquid remaining in the material 4 receding from the loop 2 after it has left the ring 9.

In the construction of FIGS. 2 and 3 liquid transfer from the material 3 to the material 4 takes place between the ends 10A and 11A of the arms 10 and 11 when the apparatus is set to the operating position as shown in FIG. 3. The apparatus of FIGS. 2 and 3 is set to the operating position by swinging the arms '10 and 11 in opposite directions towards one another until the material 3 and the material 4 are brought into contact with one another.

The construction of FIGS. 4 and 5 is set in operation by swinging the arm 17 in the direction to bring the material 4 into contact with the material 3 and the swinging action is continued until the material 3 and the material 4 are pressed around a portion of theperiphery of the pulley 23. The transfer of the liquid from the material 4 to the material 3 then takes place over the distance between the pulleys 21 and 23.

The method and apparatus are of particular advantage to the modern textile processes of treating textile materials of a cellulosic nature with pure liquid ammonia. In the present process apart from the practical difficulties of applying the pure liquid ammonia which being at 33C makes many materials lose much of the resiliency required in use, both for financial and for health reasons the ammonia removed cannot be allowed to go to waste. Large and expensive ammonia re covery plants must thus be provided at present where such ammonia treatment processes are being practised. By the method and apparatus of the present invention it has been found that a given piece of fibrous material can be impregnated with 500 to 1000 percent of its weight of pure liquid ammonia and this proportion can then be reduced to 20 percent of its weight of liquid ammonia by transfer to the incoming dry material. The amount of ammonia to be finally removed is thus reduced by a factor of 25 to 50. As most of the remaining 20 percent is required for the chemical action of the ammonia on the material the quantity of ammonia left is negligible. This negligible quantity of ammonia may be economically disposed of where conditions permit or if it must be recovered the recovery plant for a given throughput of material being treated is very much smaller and very much less expensive than the corresponding plant required in connection with the present methods of ammonia treatment.

It is to be understood that the method and apparatus of the invention are applicable with equal economy to other process such as dyeing processes and processes using materials such as acetone as impregnating materials.

The transfer of such a high proportion of impregnating liquid (about 98 percent) from the impregnated material to the dry material by the method and apparatus of the invention and especially in the short time the materials are in contact, a small fraction of a second, is remarkable and completely unexpected and is not yet fully understood although it is believed that capillary action plays a considerable part in the transfer. The capillary action is probably much enhanced by the movements of the materials particularly where they are arranged to move in opposite directions. Also, when the materials are moving in opposite directions as the material on its way from the loop becomes drier by transfer of liquid to material approaching the loop such material approaching the loop is always drier still at every point of contact.

The method and apparatus of the invention simple though they may be are an almost complete answer to the long subsisting financial problem of liquid recovery.

The main advantages conferred on the technology are:

1. Elimination or substantial reduction in the size of the recovery plant.

2. Simplification of the complete plant.

3. Reduction of labour costs in operating the plant.

4. Reduction of steam or electricity consumption for recovery purposes.

5. Reduction of capital cost of the plant.

6. Small installations become economically feasible.

What is claimed is:

1. Apparatus for producing liquid-impregnated fibrous material comprising means for feeding continuously forward material from a source of supply of unimpregnated material guiding means for guiding the forwardly moving material in a path forming a loop, means for maintaining the material approaching the loop and the material receding from the loop in contact and liquid-applying means for applying impregnating liquid to the loop over a chosen extent of the loop.

2. Apparatus as claimed in claim 1 in which the means for feeding the material comprises feed rollers.

3. Apparatus as claimed in claim 1 in which the means for maintaining the material in a path forming a loop comprises a stationary guide around which the material is led.

4. Apparatus as claimed in claim 1 in which the means for maintaining the material approaching the loop and the material receding from the loop in crossing contact comprises a single ring through which the material approaching the loop and the material receding from the loop pass from opposite sides.

5. Apparatus as claimed in claim 1 in which the means for maintaining the material approaching the loop and the material receding from the loop in side by side contact over a chosen distance comprises two spaced rings through each of which the material approaching the loop and the material receding from the loop pass from the same side.

6. Apparatus as claimed in claim 1 in which the means for applying an impregnating liquid to the loop over a chosen extent of the loop comprises a receptacle capable of containing liquid and into which the loop is arranged to dip.

7. Apparatus as claimed in claim 1 in which the means for applying an impregnating liquid to the loop comprises a spray nozzle connectible to a supply of impregnating liquid and operable to spray impregnating liquid against the loop.

8. Apparatus as claimed in claim 1 in which the means for maintaining the material approaching the loop and the material receding from the loop in mutual contact includes two arms located to be on opposite sides of the material approaching the loop and the material receding from the loop and mounted to be swingable in opposite directions towards and from one another so that each is movable to a position in which it can engage simultaneously the material approaching the loop and the material receding from the loop, the points of engagement of the said arms with the material being on opposite sides of the material and being spaced from one another.

9. Apparatus as claimed in claim 1 in which the means for maintaining the material approaching the loop and the material receding from the loop in mutual contact includes two stationary rotatable guide pulleys and a swing arm carrying a pulley, the swing arm being swingable towards and from a position in which the pulley carried by the arm engages simultaneously the material approaching the loop and the material receding from the loop at a point between the two guide pulleys. =l= 

1. Apparatus for producing liquid-impregnated fibrous material comprising means for feeding continuously forward material from a source of supply of unimpregnated material guiding means for guiding the forwardly moving material in a path forming a loop, means for maintaining the material approaching the loop and the material receding from the loop in contact and liquid-applying means for applying impregnating liquid to the loop over a chosen extent of the loop.
 2. Apparatus as claimed in claim 1 in which the meaNs for feeding the material comprises feed rollers.
 3. Apparatus as claimed in claim 1 in which the means for maintaining the material in a path forming a loop comprises a stationary guide around which the material is led.
 4. Apparatus as claimed in claim 1 in which the means for maintaining the material approaching the loop and the material receding from the loop in crossing contact comprises a single ring through which the material approaching the loop and the material receding from the loop pass from opposite sides.
 5. Apparatus as claimed in claim 1 in which the means for maintaining the material approaching the loop and the material receding from the loop in side by side contact over a chosen distance comprises two spaced rings through each of which the material approaching the loop and the material receding from the loop pass from the same side.
 6. Apparatus as claimed in claim 1 in which the means for applying an impregnating liquid to the loop over a chosen extent of the loop comprises a receptacle capable of containing liquid and into which the loop is arranged to dip.
 7. Apparatus as claimed in claim 1 in which the means for applying an impregnating liquid to the loop comprises a spray nozzle connectible to a supply of impregnating liquid and operable to spray impregnating liquid against the loop.
 8. Apparatus as claimed in claim 1 in which the means for maintaining the material approaching the loop and the material receding from the loop in mutual contact includes two arms located to be on opposite sides of the material approaching the loop and the material receding from the loop and mounted to be swingable in opposite directions towards and from one another so that each is movable to a position in which it can engage simultaneously the material approaching the loop and the material receding from the loop, the points of engagement of the said arms with the material being on opposite sides of the material and being spaced from one another.
 9. Apparatus as claimed in claim 1 in which the means for maintaining the material approaching the loop and the material receding from the loop in mutual contact includes two stationary rotatable guide pulleys and a swing arm carrying a pulley, the swing arm being swingable towards and from a position in which the pulley carried by the arm engages simultaneously the material approaching the loop and the material receding from the loop at a point between the two guide pulleys. 